Addex Therapeutics Ltd. announced that the ADX71149 (JNJ-40411813) Phase 2 epilepsy clinical study is progressing well, with Cohort 1 completed and 80% of patients recruited into Cohort 2. Results evaluating the efficacy, safety and tolerability of ADX71149 in combination with levetiracetam or brivaracetam from patient Cohorts 1 and Cohort 2 are anticipated for the second quarter of 2024. The primary efficacy endpoint of this study is time to baseline monthly seizure count. Collaboration partner Janssen Pharmaceuticals Inc., one of the Janssen Pharmaceutical Companies of Johnson & Johnson, is responsible for the clinical development of ADX71149.

As previously announced on May 10, 2023, an independent Interim Review Committee (IRC) convened by company's collaboration partner recommended to continue the study following review of unblinded data from Part 1 of patient Cohort 1. ADX71149 is a selective metabotropic glutamate sub-type 2 (mGlu2) receptor positive allosteric modulator (PAM). The multi-center Phase 2 study has been designed to assess the efficacy, safety, tolerability, and pharmacokinetics of adjunctive ADX71149 administration in patients with focal onset seizures with suboptimal response to levetiracetam or brivaracetam. The primary objective of the study is to evaluate the efficacy of ADX71149 in combination with levetiracetam or brivaracetam using a time to baseline seizure count endpoint.

Part 1 of the study evaluates the acute efficacy of ADX71149 over 4 weeks. Subjects who do not reach their monthly baseline seizure count in Part 1 continue double-blind treatment during Part 2 until they reach their monthly baseline seizure count or 8 weeks, deemed the maintenance efficacy phase. In addition, patients who complete Part 1 and/or Part 2 of the study have the option to continue treatment in the open-label extension part of the study, which evaluates the long-term efficacy and safety of ADX71149.

More information on the study can be found with Clinicaltrials.gov identifier NCT04836559.